very bad service

I bought a bed at the bedshop in 2013, on the 18 of june we had someone from the shop to come and look at our bed seeing that its giving us problems, i was told that it was not body imprint and its a fault from the factory and they will change the bed, today after how many phone calls we got someone to look at our bed again grahm, i was told that they cant exchange our bed beucouse we had a stain om the mattress and we had to pay n 1000 in for an exchange, why do i get 2 different stories? I will NEVER buy a bed from bed shop again! When u buy the bed its all stars and moon they promise but when you have n problem, they dont care